The costs of land  , engineering , site work , permits , labor , and building materials make this virtually impossible . then there are zoning issues and the rest of the politics that go along with this . 

Examples would be incorrect square footage, incorrect year built, incorrect style of home or materials.  

I'd need to go to about 250K with 10/15K in materials to get around 320K and that's pushing it.

As a seller, you HAVE TO and should declare anything that would materially affect the value of a property aka a fire.

I pay roughly $1/sq ft for material and installation.

The all-in price should be right around $12 - $15 / sq yd, which will include the carpet, padding, all misc materials and install.

As you know, material, labor, and supplies for roofing can change a lot within a matter of weeks / months. 

If that is the case, I'd get some new ones, stack them in front of the old ones, and get rebar or similar strong metal poles pounded in to hold them in place.  

I will not start work without a deposit big enough to buy the materials for that phase.

I generally use cash to invest but the real estate market is very depressed right now and my portfolio is diversified in BTC cryptocurrencies focusing mainly on gold short term trading on top of state metals